Sponge asphalt, method of producing same, and packings made therefrom



, A. C. FISCHER.

APPLlcAnoN FILED Nov.1, 1919.

SPONGE ASPHALT, METHOD 0F PRODUCING SAME, AND PACKINGS MADE THEBEFBGM.

ALBERT CHARLES FISCHER, 0F CHICAGO, ILLINOIS.

SPONGE ASPHALT, METHOD OF PRODUCING SAME, AND PACKINGS MADE THEREFROM.

Specification of Letters `Patent.

Patented Jan. 3, 1922.

Application led November 1, 191119. Serial No. 335,170.v

Sponge As halt, Method of Producing- Same, and -ackings Made'lherefrom,of which the following is a specification.

This invention is based upon the discovery that asphaltic material maybe developed into spongy, cellular form, and when so developed makes agood insulator of sound, moisture, electricity, heat at relatively lowtemperatures, and other influences; also that the material lends itselfwith peculiar advantage to application to spaces to be packed or objectsto be covered; also to ready treatment as by a heat medium for thedevelopment thereon of an impervious sealing skin and cementation toadjoining bodies.

In order that the several phases of the present invention may beunderstood, one method of producing the material, a sample of thematerial when produced, and several suggestive uses to which it may beput are illustrated in the accompanying drawings, in which- Figure l isa vertical section of a recepticle into which asphaltic material isbeing delivered under conditions which develop it into spongy cellularstructure.

Figure 2 is a perspective view of a sample of the goods produced.

Figure 3 is a sectional View suggesting a method of tamping the materialinto a lioint to be weatherproofed.

Figure 4 is a view suggesting a method of developing an impervious skinupon the eX- posed surface of the packing material.

Figure 5 suggests the use of the material as a heat insulation in thewall of a building.

Figure 6 illustrates the use of the material as ,(211, sound deadenerbeneath wooden floors; an

Figure 7 suggests the use of the material as a foundation upon which tolay paving bricks or blocks.

Referring to Figure 1, l represents a receptacle adapted to receive andhold asphaltic material in the fused state, and 2 is a container havinga nozzle 2a from which the material is delivered to the receptacle underconditions which cause the material to trap air and develop an aeratedcondition that causes it to rise to the top of the body of the asphaltcontained in the receptacle and .accumulates on the top thereof. Gravityalone may be employed for delivering the asphaltic material into thereceptacle 1, or any suitable pressure medium may be employed for thatpurpose.

3 represents a spoutthrough which the unaerated portion al, whichaccumulates in the receptacle l, may be drawn off from time to timeeither for re-melting or in order to keep the level of the accumulatingsponge asphalt below the top of the receptacle.

Preferably some means, such as the airblast 4, or a fine water spray orthe like, is directed against the upper/surface of the accumulatingspdnge asphalt in order to develop an impervious outer skin or sheaththat traps the air in the material behind the sheath until the materialis suiliciently cooled to retain its sponge-like cellular structure.

The texture of the cellular structure can be controlled, within limits,by the violence of delivery of the stream a regulated either by heightof falling, or other means of acceleration; also by the temperature atwhich it is delivered. It may also be influenced by the provision ofspecial air disseminating means, and the temperature at which the air isintroduced.

It is to be noted that the illustration in Figure l is intended toindicate at a more or less dense unaerated though fused asphalticmaterial; at A the sponge-like cellular asphalt; and between A and a1frothy or aerated asphaltic material of sufficient density to cause theglobules to rise therein. For starting the process, the receptacle 1 maybe largely filled with vfused asphalt until a body of spongy texturebegins to accumulate upon its surface, and it can then be drawn of orits level gradually lowered so as to develop the desired violence ofair- .trapping effect.

larly packed, as, for instance, the joint between two cement or otherpaving blocks 10, 11, it is advantageous to seal the outer surface ofthe packing as suggested in Figure a, as, for instance, by means of theblow torch 9, thereby developingon the packing an impervious outer skinlike the skin A4, Figures 1 and 2, and which is suggested at A4 inFigure 4. This method of sealing the ing the packing firmlyto theadjacent surfaces of the objects to be/packed. In packing such as shownin Figures 3 and 4, there is ample compressibility in the packing tocompensate for expansion of the structure under heat, and suiiicientresiliency in the material to compensate for enlargement of the packingspace by contraction of the adjacent members as a result of cold.

Figure 5 shows the material used as a heat insulation for freight cars,refrigertors, and other building structures where it is introduced as atA between the inner sheathing 12 and the outer sheathing 13.

The material of the present invention will serve well for soundinsulation in flooring, as, for instance, by introducing it as shown atA in Figure 6, where it lies between the floor boards 14 and thefoundation 15 or the cement layer 15a in which are set. the battons 16on which the boards are laid.

In this relation the material becomes an insulator against moisture aswell as sound, and it will serve well as a safeguard against buckling.of expensive wooden floors, which are sometimes injured by laying themover cement foundation before the cement has fully dried out.

Another use to which the material may be put is suggested at A in Figure7, where it serves as a substitute for the sand in which bricks are laidin paving.

'While I have illustrated the best method now known to me of developingcells in asphalt and setting it to create a spongy consistency in thematerial, this is not the only method of so doing. For instance, thecondition maybe created by aeration or causing air bubbles to rise inheated asphalt against an upper crust of chilled asphalt; or` it may bedone by chemical action causing expansion ofgases in asphalt body,followed by a cooling condition as above noted. Another method would beby evaporation or rather vaporization'of water or chemicals causingcells to form undervthe conditions of either of the foregoing recitals.Still another methodis that of blistering, according to which moistureand heated asphalt are sprayed on a surface alternately.

in any of the foregoing methods the asphalt body is caused to inherentlyexpand into many small cells, thereby causing the spongy condition todevelop.

l claim: 1. The herein-described sponge asphalt. 2. As an articleofmanufacture, an asphaltic material having a sponge-like cellu- `larstructure. outer surface also has the effect of cement- 3. As a newarticle of manufacture, asphaltic material having a cellular structurewith sluggishly sponge-like resistance to compression.

4:. The herein-described sponge asphalt having an imperforate skin.

5. Packing material comprising in its structure sponge-like cellularasphaltic material.

6. Packing material comprising in its structure sponge-like cellularasphaltic material, and having an'imperforate continuous skin.

7. ln combination withy spaced members lof a structure, a packingtherefor comprising a body of sponge-like cellular asphalt located inthe space between the bodies.

8. 1n combination with spaced members of a' structure, a packingtherefor comprising a body of sponge-like cellular asphalt located inthe space between the bodies, and having its exposed surface fused intoa continuous impervious sealing skin.

9. The art of producing sponge-asphalt which consists in deliveringfused asphaltic material under air-trapping conditions, de-

lecting the aerated asphalt.

10. rl`he art of producing sponge-asphalt Lwhich consists in deliveringfused asphaltic veloping aerated asphalt therefrom, and coliio Signed atChicago, Illinois, this 29th day 12 of Uctober, 1919.

ALBERT CHARLES FISCHER,

